United States Patent Application US 2005/0031454 A1, hereby incorporated by reference herein, describes a stator vane assembly having a plurality of stator vanes whose airfoil sections form a stagger angle with an axis of rotation. The stagger angle has a local minimum at both the airfoil root and the airfoil tip, and increases to a local maximum therebetween in order to improve the efficiency of the stator vane assembly.